Prior art systems exist which control heating and cooling of supply air to a plurality of floors or other building zones independently based on the set point of a thermostat in each zone. Conventionally, such arrangements operate by opening the damper in each zone if that zone calls for the hot or cold air which is available from a central heating/cooling system. These prior art systems are not energy efficient since they actuate the furnace or other heat source to heat the downstairs zone when the upstairs is already over heated.
It is also known in the art of building structure heating to propel air, as by means of a fan, from a lower level to an upper level. Often systems of this nature are deficient in that they require either continuous fan operation, which itself utilizes excess amounts of energy, or constant manual intervention, which is both inefficient and time consuming.
The invention disclosed in my above-identified patent application relates to a system which operates automatically to lessen the differential of temperatures in upper and lower building level interiors. The system operates by redistributing the hot air which normally rises to the upper levels of a multi-story building to a lower level, thereby providing a more uniform temperature throughout the building.